Units of time
This list below shows the units we use to measure time. It also shows the conversion from one unit to another.
\(60\) seconds = \(1\) minute
\(60\) minutes = \(1\) hour
\(24\) hours = \(1\) day
\(7\) days = \(1\) week
\(365\) days = \(1\) year (\(366\) days in a leap year)
Question
a) How many minutes are there in \(6\) hours?
b) How many hours are there in a week?
c) How many weeks make up \(63\) days?
a) \(60 \times 6 = 360\) minutes
b) \(24 \times 7 = 168\) hours in one week
c) \(63 \div 7 = 9\) weeks (there are \(7\) days in a week)
You must be careful when using fractions and decimals with units of time.
For example, \(0.5\) hours equals \(30\) minutes, not \(50\) minutes. This is because decimals show fractions of tenths, hundredths, thousandths and so on. But minutes are measured in sixtieths of an hour.
Similarly:
\(\frac{1}{4}\) hour equals \(15\) minutes
\(\frac{1}{10}\) hour equals \(6\) minutes.